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global protocol Smtp(role S, role C)
{
220() from S to C;
choice at C // Choice 0
{
Ehlo1() from C to S;
rec X
{
choice at S // Choice 1
{
250d() from S to C;
continue X;
}
or
{
250() from S to C;
choice at C // Choice 2
{
StartTls() from C to S;
220() from S to C;
// Do TLS handshake here: level below the application level protocol (like regular TCP handshake)
choice at C // Choice 3
{
Ehlo2() from C to S;
rec X
{
choice at S // Choice 4
{
250d1() from S to C;
continue X;
}
or
{
2501() from S to C;
rec Y
{
choice at C // Choice 5
{
Auth() from C to S;
choice at S // Choice 6
{
235() from S to C;
rec Z1
{
choice at C // Choice 7
{
Mail() from C to S; //Mail from:<a@b.com>
choice at S // Choice 8
{
501() from S to C;
continue Z1;
}
or
{
2502() from S to C;
rec Z2
{
choice at C // Choice 9
{
Rcpt() from C to S; //Rcpt to:<c@d.com>
choice at S // What is this choice??? // Choice X
{
2503() from S to C;
continue Z2;
}
}
or
{
Data() from C to S;
354() from S to C;
too from C to S; //to:<you>
froom from C to S; //from:<me>
rec Z3
{
choice at C // Choice 10
{
DataLine() from C to S;
DataLine() from C to S;
continue Z3;
}
or
{
Subject() from C to S; //Subject:<my Subject>
Subject() from C to S; //Subject:<my Subject>
continue Z3;
}
or
{
EndOfData() from C to S; // CRLF.CRLF
2504() from S to C;
continue Z1;
}
}
}
}
}
}
or
{
Quit5() from C to S;
221() from S to C;
}
}
}
or
{
535() from S to C;
continue Y;
}
//.. 501 Invalid base64 Data
}
or
{
Quit4() from C to S
}
}
}
}
}
or
{
Quit3() from C to S;
}
}
or
{
Quit2() from C to S;
}
}
}
}
or
{
Quit1() from C to S;
}
}